continue refactor of backend to utilize ts, deprecate js

server/src/routes/query.ts

@@ -0,0 +1,94 @@
+'use strict';
+
+import { Router, type Request, type Response, type NextFunction } from 'express';
+import logger from '../logger.js';
+import { embedTexts, search, rerank } from '../services/retrievalService.js';
+import { generate } from '../services/generationService.js';
+import { computeGroundedness } from '../services/scoringService.js';
+import * as notebookStore from '../stores/notebookStore.js';
+
+const TOP_K_SEARCH = 20;
+const TOP_K_RERANK = 5;
+
+const router = Router();
+
+interface QueryBody {
+  notebookId?: string;
+  question?: string;
+}
+
+router.post('/', async (req: Request<unknown, unknown, QueryBody>, res: Response, next: NextFunction) => {
+  try {
+    const { notebookId, question } = req.body;
+    if (!notebookId || !question) {
+      res.status(400).json({ error: 'notebookId and question are required' });
+      return;
+    }
+
+    logger.info({ notebookId, question }, 'query received');
+
+    const [queryEmbedding] = await embedTexts([question], 'query');
+
+    const searchResults = search(queryEmbedding, notebookId, TOP_K_SEARCH);
+    if (searchResults.length === 0) {
+      res.json({
+        answer: 'No sources found for this notebook. Upload some documents first.',
+        citations: [],
+        groundednessScore: null,
+        followUpQuestions: [],
+      });
+      return;
+    }
+
+    const candidateChunks = searchResults.map((r) => r.chunk);
+    const reranked = await rerank(question, candidateChunks);
+    const topChunks = reranked.slice(0, TOP_K_RERANK).map((r) => r.chunk);
+
+    logger.debug(
+      {
+        searchHits: searchResults.length,
+        rerankedTop: topChunks.length,
+      },
+      'retrieval complete'
+    );
+
+    const sourceGroups = notebookStore.buildSourceGroups(notebookId, topChunks);
+
+    const { answer, citedSourceIndices, followUpQuestions } = await generate(question, sourceGroups);
+
+    const citedChunkIds: string[] = [];
+    for (const idx of citedSourceIndices) {
+      const group = sourceGroups.find((g) => g.docIndex === idx);
+      if (group) {
+        citedChunkIds.push(...group.chunks.map((c) => c.id));
+      }
+    }
+
+    const groundednessScore = await computeGroundedness(answer, citedChunkIds);
+
+    logger.info({ groundednessScore: groundednessScore.toFixed(3) }, 'query complete');
+
+    const citations = citedSourceIndices.map((idx) => {
+      const group = sourceGroups.find((g) => g.docIndex === idx);
+      return group
+        ? {
+            sourceIndex: idx,
+            sourceId: group.sourceId,
+            name: group.name,
+            chunkTexts: group.chunks.map((c) => c.text),
+          }
+        : { sourceIndex: idx, sourceId: null, name: null, chunkTexts: [] };
+    });
+
+    res.json({
+      answer,
+      citations,
+      groundednessScore,
+      followUpQuestions,
+    });
+  } catch (err) {
+    next(err);
+  }
+});
+
+export default router;